Depth-indicating device



H. W. KING.

DEPTH INDICATING DEVICE.

APPLICATION FILED APR. I, 1920.

Patented July 18, 1922.

@Men/co4,

ancianas UNITED STATES PATENT OFFICE.

DEPTH-NDICATING DEVICE.

Application filed April 1 1920.

T0 all wlw/m, t may concern:

Be it known that l, Hon/ion 1V. lime, a citizen olf' ghe lnited States oi" merica, residing at Ann Arbor, in the county ot lVashtenaw and State of Michigan, have invented certain new and useful Improvements in Depth-indicating Devices, ot which the 'Folk lowing is a specification, reference being had therein to the accompanyingdrawings. Y The invention relates to devices tor indicating the depths ot liquids and is particularly applicable to motor vehicles for indieating the depth of the liquid `fuel in the 'fuel tank.

The invention has tor one et its objects the provision ot means `tor drawing air into a chamber within the tank and communieating with the liquid fuel at the full depth to be measured and ot means permeable to air and substantially impermeable to the liquid fuel for preventing the liquid fuel from. beinedrawn through the suction pipe which is connected to the fuel tank. Another object oit the invention is the provi sion of a unit detachably mounted upon the tank and comprising the air chamber and means for preventing the liquid. tuel from being drawn thrown the suction pipe. Further objects of the invention reside in the novel arrangements and combinations ot parts as more 'Fully hereinatter set forth.

In the drawings:

Figure 1 is a longitudinal sectional view, partly in elevation, of a construction cmbodying my invention; l

Figure 2 is a top plan view oi" a portion oi a tank containing the liquid tucl to be measured and showing the top ot that portion oiE the depth indicating device which is mounted upon the tank.

l is a tank containing liquid iuel, such as gasoline, and 2 an internal combustion en gine intake manifold of a motor vehicle.

3 is an air chamber formed by a tube 4 having a closed upper end and depending vertically from the top ot the tank 1, the lower end of this tube being open and terminating adi acent to the bottom ot the 'tank 1. 5 is a tube having its upper end communicating with the air outside the tank 1 and its lower end communicating with the interior of the tube et at substantially the same level as this tube communicates with the gasoline in the tank. The tube 5 pret erably extends longitudinally within the tube 4;, For producing a vacuum in the tank Specification Letters Patent.

Patented July 18, 1922.

serial No. 370,417.

1 suliicient to draw air through the tube 5 the suction pipe 6 is provided connecting into the intake manifold 2 and into the top et the tank 1. 7 is a suitable pressure gauge such as a U gauge having the legs 8 Kand 9 which are respectively connected to the pipes 10 and 11 tor transferring the pressure of the air in the tube 4l and in the tank 1, respectively.

In order to prevent the drawing of gasoline from the tank 1 through the suction pipe 6 and into the intake manifold 2, in the event that the tank is substantially :full and some et the gasoline may splash upwardly adjacent to the connection et the suction pipe, the following construction is provided. 12 is a dome upon the top ot the tank 1, this dome having the annulai,1 shoulder 13. 14e is a diaphragm permeable to air but substantially impermeable to gasoline, this diaphragm extending transversely ot the dome 12 and being secured between the annular shoulder 13 and the nut 15 threadedly engaging the interior o'l` the dome and having the passage way 16 therethrough. The suction pipe 6 is detachably connectedto the top ot this dome as by means ot the union 17 securing the pipe to the nipple 15%. Suitable `fibrous material such as telt, may be provided upon the upper side ot the diaphragm 14- for supporting the latter, this material also being adapted to absorb any gasoline which might pass through the diaphragm. i

ln order to readily detach that portion of the depth indicating device mounted on the tank 1 thc cover or cap 2() is provided to which the tubes 3 and 4i aud the dome 12 are secured, the latter being preferably integral. with the cover or cap. The nipples 21 and 22 to which the pressure pipes 10 and 1l are respectively connected by suitable unions are also mounted upon this cover or cap in position to communicate respectively with the interiors ot the tube 4 and tank 1, 23 is a securing member having the annular base flange 24 iXedly secured upon the top of the tank 1 and the cylindrical eX- ternally threaded 'flange 25. 26 is a nut threadedly engaging this flange and having at its outer end the inwardly extending flange 27 engaging the outer peripheral surtace o'f the cover or cap 2O and adapted to force this cover or cap toward the end of the cylindrical lange 28 is a suitable packing between the cover or cap and the outer end oi" the cylindrical flange 25 for making an air tight joint.

ln operation the suction in the intake maniiiold 2 draws air from the interior of the gasoline tank l through the pipe 6, when the engine'is running. Due to the partial vacuum in the tank, airis drawn through the inner tube 5, Which air enters the outer tube l at substantially the level ot' the point oif communication thereof with the gasoline and displaees the gasoline trom this outer tube. The pressure of this air counterbalances the hydrostatic head of the gasoline down to the lower end ci? the outer tube and When transferred to a suitably graduated gage Z indicates the depth or amount of the gasoline. rlhe diaphragm 14 permits of the passage of air into the pipe 6, but prevents substantially the passage of gasoline thereinto. The fibrous materialL 19 absorbs any small amount ot gasoline which might pass through the diaphragm and additionally supports the diaphragm.

What 1 claim as my invention is: n

E,1. In a depth indicating device for liquids, the combination with a closed tank containing a liquid, of a chamber communicating With the air outside said tank and with the liquid in said tank, a suction pipe connected to said tank 'forproducing a. vacuum therein sufficient to draw air into said chamber for displacing the liquid down to the point oi communication of saidchamber With the liquid, means for prevent-ing the passage of the liquid from said tank through said suction pipe, and a pressure gage in communication with said tank above the level of the liquid therein.

.2. In a depth indicating device :for liquids, the combination with a closed tank containing a liquid, oi a chamber communicating With the air outside said tank and with the liquid in said tank, a suction pipe communicating with said tank tor producing a vacuum therein su'ilicient to draw air into said chamber for displacing the liquid down to the point oit communication ot said chamber with the liquid, a member in the communication between said suction pipe and tank, said member being permeable to air and substantial] y impermeable to the liquid, and: a pressure gage in communication With said tank above the level of' the liquid therein.

3. In a dept-h indicating device for liquids, the combination With a closed tank containing a liquid, of a` chamber communicating with the air outs-ide said tank and With the .liquid in said tank., a dome upon said tank,

a source of vacuum, a pipe connected to said source of vacuum and said4 dome, a diaphragm extending across said dome permeable to air and substantially impermeable to the liquid Ator preventing the liquid being dravi'fn into said source of vacuum, and a. l

pressure gage in communication with said tank above the level el? the liquid therein.

l 4l. ln a depth indicating device tor liquids, the combination With a closed tank containing a liquid, of a chamber communieating` with the air outside said tank and with the liquid in said tank, a dome upon said tank, a source or vacuum, a pipe connected to said source et vacuum and said dome, a diaphragm extending across said dome permeable to air and substantially impermeable to the liquid, fibrous material onV the upper side ot said diaphragm forming a. support therefor and adapted to absorb any liquid passing therethrough, and a pressure gage in communication with said tank above the level of the liquid therein.

5. The combination With a closed tank containing a liquid, of a device for indicating the depth' of the liquid in said tank compris-ing a tube extending into said tank and having an open lower end terminating near the bottom thereof, a cover or cap for closing the upper end of said tube, said cover or cap being removably secured to said tank, ay second tube extending longitudin'ally Withinr said Hist-mentioned tube and having an open lower end terminating near the bottom of said tank and an open upper end communicating with the air outside said cover or cap, a dome u on said diaphragm and a pressure gauge Jfor indi eating the difference in pressures of the air inside said first mentioned tube and inside said tank.

6. The combination with avclosed tank, containing a liquid and an' intake manifold, ot a. detachable device for indicating the depth ot the liquid in said tank comprising a cover or cap, a nut fory detachably securing said cover or cap to the top ot' said tank, a chamber secured to said cover or cap and communicating With Athe liquid in said tank at the full depth to be measured, a tube secured to said cover or cap and communicating With the air out-side the same and With the interior of said chamber at Vsubstantially its pointA ot 4communication With the liquid, means detachably securedV to said cover or cap 'for indicating the diiference of. pressures 'ot the air in said air chamber and tank, and a suction pipe detachably communicating With said intake manifold and detachably connected to said cover or cap for effecting sufficient vacuum in said tank to dravv air through said tube into said air chamber to displace the liquid therefrom. ,i

In testimony Where'ot 1 aiiix my` signature.

Heerlen' W, KING, 

